Based on the advanced technique of self-balancing test, the bearing characteristics of large-diameter deep rock-socketed pile（hr/d>30）, including the relation of load and displacement on top of it, side friction, the tip resistance and so on, under 10 thousand-ton load level in argillaceous area had been analyzed according to the report of static loading test on 2-piles of Balinghe River Bridge and 1-pile of Beipan River Bridge. The results indicate that Q-s curve of large diameter pile in mudstone declines slowly, and the weathering level of rock has great impact on tip resistance of pile. The ultimate bearing capacities of sandstone and dolomite in puny weathering are stronger than that of limestone in weak weathering; the side friction of pile is closely related to relative displacement of pile-soil interface, and the side resistance of pile in argillaceous dolomite needs smaller pile-soil relative displacement. Finally, the ultimate values of lateral resistance of pile and estimate of exploration report have been comparative analyzed.